“So, again, you’ve defined what isn’t the problem. You’ve also acknowledged Lashon Hara is assur. So, in your esteemed opinion, a frum man who regularly speaks Lashon Hara– which, admittedly, isn’t an clinical addiction as you’ve eloquently pointed out — how is he to stop engaging in that issur? What would you recommend to your best friend who confided to you he has this problem? (You agree it is a problem for a Yid, don’t you?)”
I would recommend to learn Mussar. In addition, I would suggest to start slow (perhaps being extra careful 1 hour a day) and grow from there.